SO₂ Capture and Detection by SBA-15 and Amine-Functionalized SBA-15

An exploration of the SO2 adsorption properties, of two distinct mesoporous materials, classic hydroxy-functionalized SBA-15 and amino-functionalized SBA-15, shows remarkable SO2 adsorption properties, with total uptakes of 4.43 and 4.19 mmol g(-1) at 298 K and 1 bar, respectively. Furthermore, the amino-functionalization increases the SO2 adsorption at low pressure. Relatively weak SO2 interactions via physisorption processes in both materials were corroborated by calculating the heat of adsorption for SO2. Then, photoluminescence experiments demonstrated the outstanding properties of SBA-15 for selective SO2 detection. A higher packing of the SO2 molecules within the pores of the materials was the driving force for the change in fluorescence. Finally, the time-resolved photoluminescence decay experiments provide insights into the intricate host-to-guest energy transfer mechanisms intrinsic to these materials. This research not only advances our knowledge of SO2 adsorption mechanisms but also underscores the potential applications of SBA-15 materials in gas sensing and environmental monitoring, which are crucial in various industries.